The Diamond Blackfan Anemia Registry (DBAR) is a comprehensive database of patients with the rare inherited bone marrow failure syndrome, Diamond Blackfan anemia (DBA). DBA is a heterogeneous genetic disorder characterized by pure red cell aplasia, congenital anomalies and a predisposition to cancer. Anemia usually presents in infancy or early childhood and approximately 50% of patients have at least one congenital anomaly. The overall cumulative incidence of cancer is over 20% by age 46, with some individual cancer risks such as colon carcinoma and osteogenic sarcoma elevated more than 30-fold compared to the general population. To date, 11 genes encoding ribosomal proteins of both the small and large subunits have been found to be mutated, representing nearly 70% of patients with DBA. Affected individuals within the same family vary dramatically as to the degree of anemia, response to corticosteroids, the presence of congenital anomalies, and the development of cancer. Prior to the development of the DBAR, our knowledge regarding the epidemiology and response to various treatment modalities was determined exclusively from literature reports. The DBAR was developed in order to provide a well-characterized patient substrate linked to biological samples, permitting the study of the epidemiology and biology of DBA. The objective of this proposal is to continue to improve and exploit the DBAR in order to: 1) facilitate investigations into the epidemiology and biology of DBA 2) provide an accurate phenotype of DBA patients to facilitate genotype-phenotype correlations as new genes are discovered 3) provide well-characterized patients access to treatment protocols 4) provide patients and their health care providers access to research studies 5) provide patients and their health care providers with results of research studies 6) serve as a resource to patients and their doctors to guide diagnostic, therapeutic, and reproductive decisions 7) develop an accurate, rapid diagnostic test for DBA 8) utilize the DBAR infrastructure and patient data to develop and manage clinical trials 9) solicit national and international collaborative research